1. Field of Invention
This invention relates to the recovery of low, medium and high boiling components from mixtures containing same. In one of its aspects, this invention relates to recovery of ethylene from ethylene containing streams. In another aspect, the invention relates to the recovery of ethylene from the effluent of an ethane cracking unit. In yet another aspect, the invention relates to fractional distillation apparatus.
2. Prior Art
Fractional distillation processes are widely employed for the separation of hydrocarbons of different boiling points. A common problem encountered when it is sought to separate unsaturated hydrocarbons by fractional distillation is the propensity for the contents of the distillation kettle bottoms to foul or form gum as the temperature of the distillation kettle rises. Because of the tendency of the kettle bottom materials to form gum, a spare reboiler kettle is generally kept available to allow for off-stream cleaning of the fouled reboiler kettle. However, off-stream cleaning of the fouled reboiler kettle still requires unit down-time in order to switch the clean reboiler kettle for the fouled reboiler kettle.